Clinical aspects of non-Hodgkin's lymphomas presenting with discordant histologic subtypes.

From July 1971 to December 1980, 323 cases of non-Hodgkin's lymphoma were randomized into prospective clinical trials at Stanford University Medical Center. Analysis of these cases revealed 30 patients (9.3% of the total) with disease of different histologic subtypes at separate anatomic sites (discordant lymphomas). On further analysis, 16 of these patients (4.8% of the total) were found to have disease of different histological and prognostic types. Recommendation is made that initial therapy be directed at the poor-prognosis component of these tumors. Relapses of both favorable prognostic types and unfavorable histologic types were seen, and further biopsy at the time of relapse is recommended in these cases.